Solid, stable diazonium compounds



United States Patent The present invention relates to new solid, stablediazonium compounds and to a process for preparing the same; moreparticularly, it relates to solid, stable diazonium compoundscorresponding to the following general formula:

wherein A and B represent radicals of the benzene or naphthalene series,and -N R represents the radical of a diazonium salt. T

We have found that solid, stable diazonium compounds are obtained bydiazotizing in known manner amines corresponding to the general formula:

wherein A and B represent radicals of the benzene or naphthalene seriesand separating the diazonium compounds in solid form in a manner knownin itself.

The new diazonium compounds may be separated, for example, as diazoniumchlorides, diazonium phosphates, diazonium sulfates, diazoniumarylsulfonates, diazonium tetrafiuoroborates or diazonium chloride-metalchloride double salts. They, generally, possess a good solubility and anextraordinarily high stability, properties which are independent orsubstantially independent of the mode of separation but depend on thespecial constitution of the compounds used as starting material.

After storage for 4 weeks at 40 C., which is standard for the stabilityof those compounds, the compounds obtained according to the inventionshow no decrease in the content of pure substance. After storage forseveral months at 40 C. or even 50 or 60 C., no substantial decrease inthe content of pure substance is observed. Even mixtures of the newdiazonium compounds with such metal salts as generally decomposediazonium compounds with evolution of nitrogen, for example with coppersalts, possess a good stability when stored in the hot.

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The following table shows the results obtained by the storage in the hotof several diazonium compounds:

Decrease in the content 7 of pure substance in percent of the initialvalue Conditions Diazonium-naphthalene-l, 5-disulfonate of 2-(2-amino-4-methoxy-5 -methylphenyl)-benztriazole-1-oxide.

Diazonium-naphthalene-l, fi-disulfonate of 2-(2-amino-4-rnethoxy-5-methylphenyl)-benztriazole-1-oxide and coppersulfate (molar ratio 1:

Diazonium tetrafluoroborate of 2-(2-amino- Diazonium tetrafluoroborateof 2-(2-' amino- F-methoxy-5-methylphenyl)- bGHZlZIlELZOlG -LOXldG withcopper sulfate (molar ratio 1: 1.5).

Diazonium sulfate of 2-(2-amino-4- methoxy-5-methylphenyl)-benztriazole-1-oxide.

Diazonium sulfate of 2-(2-amino-4'-methoxy-5-methylpheuyl)-benztriazolel-oxiggewith copper sulfate (molarratio 30 days, 50 C.

Diazonium chloride-zinc chloride double salt of2-(2-amin0'4-methoxy-5-methylphenyl)-bcnztriazole-1-oxide.

Diazoniurn chloride-zinc chloride double salt of 2-(2-amino-4,5-diethoxyphenyl)- G-methylbenztriazole-l-oxide.

Diazonium chloride-zine chloride double salt of 2-(2-amino4-methoxy-5Tacetylamidnophenyl)-6-rnethylbenztriazole-1- or! e,

Diazonium chloride-zinc chloride double salt of 2-(2-amino-4-1nethoxy-5-acetylarninopheuyl)-6-n ethylbeuztriazole-l-oxide and copper sulfate.

Diazonium chloride-zinc chloride double salt of2-(2'-amiuo-4'-acetylamino-5- methylphenyl)-6-methylbenztriazole-1-Diazonium chloride-zinc chloride double salt of2-(2-amino-4-methoxy-5-aeetylaminophenyl)-benztriazole-l-oxide.

Diazonium chloride of 2-(2-amino4- ruethoxy-5-'benzoylaminophenyl)-benztriazole-l-oxide and copper sulfate.

30 days, 1. 1

130 days, 2.0

60 days 0 130 days, 2.8

days, 1.6

30 days, 0

The new diazonium compounds represent valuable intermediate products forthe manufacture of azo dyestuffs.

As starting compounds for the process according to the invention, amineshaving the above formula are used in which the benzene or naphthaleneradicals A and B may contain halogen atoms, trihalogen alkyl, alkyl,aryl, alkoxy, aryloxy, cyano, carboxylic acid amide, carboxylic acidester, sulfonic acid amide, sulfonic acid ester, alkylsulfonic,arylsulfonic, alkylamino, arylamino, acylamino or acyl groups. Thesecompounds are obtained, for example, according to the process describedin US. patent application Ser. No. 13,710, 1960.

The following examples serve to illustrate the invention but they arenot intended to limit it thereto, the parts being by weight unlessotherwise stated and the relationship of parts by weight to parts byvolume being the same as that of the kilogram to the liter:

Example 1 270 parts of2-(2-amino-4'-methoxy-5'-methylpheny1)-benztriazole-1-oxide are stirredwith 1500 parts by volume of water and converted into the hydrochlorideby adding 1200 parts by volume of hydrochloric acid of 20 B. andstirring for an hour. After having added ice,

a the batch is diazotized in the usual manner by introducing 200 partsby volume of a N-sodium-nitrite solution.

Then, a solution of 350 parts of the sodium salt ofnaphthalene-1.5-disulfonic acid in 3500 parts by volume of water areadded to the clear red-brown diazonium solution obtained, whereby thediazonium naphthalene-1.5- disulfonate is precipitated in the form oflight-yellow crystals, the precipitation being completed by adding 1000parts of sodium chloride. The crystalline precipitate issuction-filtered, Washed with a solution of sodium chloride and dried at40 C.

Example 2 348.5 parts of 2-(2'-amino-4,5'-diethoxyphenyl)-6-chlorobenztriazole-l-oxide are introduced, while cooling, into 400 partsof concentrated sulfuric acid. 304 parts of nitrosylsulfuric acid of41.9% strength are added dropwise, the temperature being maintainedbelow 50 C. by external cooling and regulation of the dropping rate.Then, the batch is stirred for 1 hour and poured on to ice. By addingsodium sulfate the diazonium sulfate is precipitated, suction-filteredand dried. It represents a light-yellow crystalline powder.

Example 3 270 parts of2-(2'-amino-4'-methoxy-S'-methylpl1enyl)-benztriazole-1-oxide arediazotized as described in Example l. The solution of diazonium chlorideis diluted with Water to 6000 parts by volume; after having added anaqueous solution of 110 parts of sodium borofluoride, the diazoniumfluoroborate precipitates in the form of red crystals, the precipitationbeing completed by adding sodium chloride. Then, the precipitate issuction-filtered, washed with a 15% solution of sodium chloride anddried at 40 C.

Example 4 327 parts of 2-(2-amino-4'-methoxy-5'-acetylaminophenyl)-6-methyl-benztriazole-l-oxide are stirred with 700 parts by volume ofwater. Then, 1200 parts by volume of hydrochloric acid of B. are added.As soon as the hydrochloride has formed, ice is added and the batch isdiazotized with 200 parts by volume of an aqueous 5 N-sodium nitritesolution. The diazom'um solution is diluted with water to 6000 parts byvolume; then, an aqueous solution of 75 parts of zinc chloride is slowlyadded dropwise. The diazonium chloride-zinc-chloride double saltprecipitates in the form of red crystals, the precipitation beingcompleted by adding sodium chloride. The precipitate issuction-filtered, washed with a 15% solution of sodium chloride anddried at 40 C.

4;. Example 5 by adding 2000 parts of sodium chloride. The diazoniumchloride is suction-filtered, washed with a 15% solution of sodiumchloride and dried at 40 C.

We claim: 1. The solid stable diazonium compounds having the followingformula V /N i Y wherein X and Y represent members selected from thegroup consisting of methyl, methoxy, ethoxy, acetylamino andbenzoylamino, Z represents a member selected from the group consistingof hydrogen, chlorine, methyl and methoxy, and N R represents a radicalselected from the group consisting of diazonium chloride, diazoniumsulfate, diazonium tetrafluoroborate, diazonium naphthalene disulfonateand diazonium chloride-zinc chloride.

2. The solid stable diazonium compound having the formula /N\ onReferences Cited in the file of this patent UNITED STATES PATENTS Re.17,306 Laska et al. May 28, 1929 1,342,134 Schedler June 1, 19202,501,188 Parker et al. Mar. 21, 1950

1. THE SOLID STABLE DIAZONIUM COMPOUNDS HAVING THE FOLLOWING FORMULA